Here are the instructions for all consoles according to this Forbes article. I REPEAT, IT WORKED FOR all consoles!

https://www.forbes.com/sites/brianmazique/2020/11/06/how-to-fix-the-madden-21-sign-in-issue/?sh=63b1c036235b

Xbox One

Close the Madden NFL 21 application from the Xbox One Dashboard

Select Options > Manage Game and Addons for Madden

Navigate to "Saved Data"

Navigate to "Reserved space"

File should be roughly 4GB

Select options for that file

Select clear reserved space

Confirm the action by selecting CLEAR RESERVED SPACE

Restart your Xbox One

Launch Madden NFL 21

PS4

Close the Madden NFL 21 application

Select Options on Madden NFL 21

Navigate to "Delete"

Confirm deletion

Insert your Madden NFL 21 disc, and launch OR Reinstall the game from the Playstation Store if purchased digitally

Install Madden NFL 21

Once fully updated, launch Madden NFL 21

PC

Close the Madden NFL 21 application

Wait for it to close completely

Navigate to this file directory

C:\ProgramData\Frostbite\Madden NFL 21\LCU

Delete the LCU folder

Right click the folder and select Delete

Restart your system

Launch Madden NFL 21